Treasury of Scripture Knowledge
Now Moses kept the flock of Jethro his father-in-law, the priest of Midian: and he led the flock to the west side of the desert, and came to the mountain of God, even to Horeb.
And Jethro, Moses' father-in-law, came with his sons and his wife unto Moses into the wilderness, where he encamped at the mount of God:
And when forty years were expired, there appeared to him in the wilderness of mount Sinai an angel of the Lord in a flame of fire in a bush.
Which things are an allegory: for these are the two covenants; the one from mount Sinai, which brings forth to bondage, which is Hagar.
And they departed from Rephidim, and encamped in the wilderness of Sinai.